The purpose of the Submacular Surgery Trials (SST) is to evaluate surgical removal of subfoveal choroidal neovascular lesions secondary to age-related macular degeneration, which is the most prevalent cause of irreversible severe vision loss in Americans over 65, ocular histoplasmosis, and unknown causes in four randomized clinical trials, each for a different lesion type and presumed etiology. Only one eye (study eye) of each patient is expected to be eligible for one of the four SST clinical trials. Patients assigned at random to the control arrn will be managed by either observation (no treatment) or laser photocoagulation, depending upon the type of lesion and the findings from earlier clinical trials of treatment of choroidal neovascularization. The primary outcome for each trial will be change in visual acuity of the study eye from baseline to the two-year examination, with better or same visual acuity as at baseline deemed a successfitl outcome. The principal secondary outcome will be change in health-related quality of life from baseline to the two-year interview, as assessed using the Medical Outcomes Study SF-36 questionnaire. Other outcomes of particular interest include adverse events, such as repeated surgery or other treatment of the study eye and loss of measurable visual acuity in the study eye. A parallel economic analysis of surgical management will be undertaken. Patients will be evaluated for eligibility, treated, and followed for clinical outcomes at 50 to 55 collaborating clinical centers. Other SST centers will be the Study Chairman's Office, responsible for overall leadership and direction of the SST; the SST Coordinating Center, responsible for providing scientific leadership and logistic support to the SST investigative team; and the SST Photograph Reading Center, responsible for assessing the ability of the ophthalmologists to identify and enroll eligible patients and to adhere to the treatment protocol. 1600 patients will be enrolled in the SST in a two-year period and randomly assigned to one of the two treatment arrns of the trial for which eligible by personnel at the SST Coordinating Center. An independent Data and Safety Monitoring Committee will review the data at least twice each year to assess the risks and benefits of surgery. This application is for funding to support the activities of the SST Study Chairman's Office.